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Enteric Bacterial Invasion Of Intestinal Epithelial Cells In Vitro Is Dramatically Enhanced Using a Vertical Diffusion Chamber Model
Published on: October 22, 2013
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Norepinephrine increases the pathogenic potential of Campylobacter jejuni
T A Cogan1, A O Thomas, L E N Rees
1Division of Veterinary Pathology, Infection and Immunity, School of Clinical Veterinary Science, University of Bristol, Langford, Bristol BS40 5DU, UK. tristan.cogan@bristol.ac.uk
Gut
|December 23, 2006
Summary
Norepinephrine (NE) exposure increases Campylobacter virulence. This stress-related factor enhances bacterial growth, motility, and invasion, potentially worsening infections and explaining disease variability.
Area of Science:
- Microbiology
- Infectious Diseases
- Gastroenterology
Background:
- Campylobacter jejuni causes various human gastrointestinal illnesses.
- Intestinal norepinephrine (NE) levels rise during stress, potentially entering the gut lumen.
- NE is known to promote bacterial growth and enhance pathogen virulence, such as in Escherichia coli.
Purpose of the Study:
- To investigate the impact of NE on the pathogenic potential of C. jejuni.
- To understand how stress-related factors influence C. jejuni virulence.
Main Methods:
- C. jejuni cultures were grown in iron-replete and iron-limited media.
- The effect of 100 microM NE on bacterial growth was assessed.
- Virulence factors, including motility and epithelial cell invasion, were measured.
Main Results:
- NE significantly increased C. jejuni growth rate, motility, and invasion of epithelial cells under iron-limited conditions.
- NE-exposed bacteria caused more significant disruption of epithelial cell monolayers.
- Widespread breakdown of tight junctions was observed in NE-exposed cultures.
Conclusions:
- Norepinephrine exposure enhances C. jejuni virulence-associated properties.
- Host stress and associated NE increase may contribute to the severity and variability of C. jejuni infections.
- This highlights a potential mechanism linking host physiological state to bacterial pathogenesis.
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